McDonald’s has launched two new limited edition Big Macs to celebrate the iconic burger’s 50th anniversary.

The Grand Big Mac and Mac Jrn will be available in restaurants as of today and are bigger and smaller versions of the classic burger.

The supersize Grand Big Mac is a larger version of the original and includes bigger sesame topped buns, bigger beef patties, two slices of cheese and all the usual toppings.

It also comes in at a whopping 741kcal per serving and costs £3.99.

For diners with a smaller appetite however, the Mac Jrn is a smaller version of the traditional Big Mac burger which includes one beef patty, a slice of cheese, and the sauce.

It has 400kcal per serving and costs £2.19.

The news comes after McDonald’s recently announced that it would be selling healthier low calorie meals that come in at less than 600 calories per meal.

Steven Howells, head of marketing at McDonald’s UK said: ‘As an iconic McDonald’s product, we are proud and excited to be celebrating 50 years of the legendary Big Mac and for the first time ever in the UK, introducing the two new sizes for a limited time.

‘We know a lot of our customers will remember the 1974 launch of the Big Mac in the UK and have continued to enjoy the burger and pass the Big Mac love on since then, it remains our most iconic burger!’

Created by McDonald’s franchise owner Jim Delligatti and officially launched by the burger chain in 1968, the Big Mac went on to become one of the takeaways’ most popular burgers and in 2007 it was reported that a Big Mac was sold every 17 seconds in the US – or around 550 million every year.